This invention relates to ventilating apparatus for exchanging air flow between an interior space and an exterior space.
It is known to provide ventilating apparatus for buildings. One type of ventilating apparatus is adapted to be mounted relative to a glazed panel of a building whereby air is exchanged between an interior space of the building and atmosphere outside the building. An aperture is provided in the glazed panel for receiving the ventilating apparatus. Generally, the apparatus comprises a cylindrical housing having an outwardly circumferentially extending flange and a fan rotatably mounted on a central longitudinal axis of the housing. The housing is provided with a shutter mechanism for controlling flow of air through the housing. The outer circumferential surface of the housing is provided with an axially extending thread adjacent the flange and is thereby adapted to co-operate with an annular member having an axially extending thread on an inner circumferential surface thereof.
The aperture is the glazed panel has a diameter greater than the external diameter of the cylindrical housing but less than the external diameter of the flange of the housing. The housing is inserted through the aperture so that a rear surface of the flange abuts an adjacent surface of the panel. The annular member then is mounted on a portion of the housing projecting from an opposite surface of the glazed panel and the annular member is screwed axially of the cylindrical member so that the flange of the housing and the annular member are secured in abutment with inner and outer surfaces respectively of the glazed panel.
Although such ventilating apparatus is suitable for use with a single glazed panel, the apparatus is not suitable for multi-glazed panels used in the building industry.